Do imperial stouts always ferment like crazy?

[Zephyr259]

I often see photos of imperial stouts with the krausen bursting out of the fermenter and it's making me reconsider my next brew's logistics.

I was intending on brewing a small 10L batch as that will give me around 30 bottles of a stout which will hopefully be around 10%. However, I ferment my small batches in a Spiedel 12L fermenter, it's a screw top barrel with a really big bubbler airlock on top and it mostly copes fine at 10L but if the stout is going to generate mad krausen then it may not be suitable.

My other option is either a 15L bucket but then I have to mess about with a siphon at the end and I haven't used my siphon in over a year so it might have gone a bit funny. Or I scale up and do my usual 15L batch in my full size conical. A side benefit to scaling up is the grain bill hits a level where a reiterated mash should work in the GF, 10L means half the grain bill would be so small that the wort wouldn't overflow and that can cause the pump to run dry like on my recent 60/-.

Any experiences with escaping krausen on an imperial stout?

 

[kodak79]

Every big beer I've done (RIS and Grand Cru) have blown out the top of the fermenter - the RIS in a big way. I had about 50% extra space in the fermenter and it went mad.
So I'd go for as big a vessel as you can.

 

[Broken Toe]

I've done two imps and they have both blown off. The first took my lid off, so for the second I installed two blow off tubes in anticipation, I'm glad I did. It went like the clackers. I agree with @kodak79, big bucket.

 

[Brewdogpunk]

I’m planning to have a go by combining a Youngs American Mocha Porter with a Coopers Stout, so doubling up the malt extract and some additional sugar and a a little espresso for flavour
Anyone got any thoughts as to whether this is likely to go nuclear?
Anyone got any thoughts as to whether it will even work?

 

[Leon103]

Anything I brew with dark malts ends up climbing out of the fv

 

[Rodcx500z]

I’m planning to have a go by combining a Youngs American Mocha Porter with a Coopers Stout, so doubling up the malt extract and some additional sugar and a a little espresso for flavour
Anyone got any thoughts as to whether this is likely to go nuclear?
Anyone got any thoughts as to whether it will even work?

More like a proton torpedo

 

[BeerCat]

Not a good idea. I would use at least a 20l or try fermenting it cold with lager yeast. Probably still go off though.

 

[An Ankoù]

It must the time of year or the alignment of the planets or something. I did 24 litres of american wheat beer, OG 1057, with MJ M42 in a 30 litre fermenter and I had to remove the blow off device and just invert a glass over the bung hole. As well as loosening the lid all round. Ambient temp about 16-18 C. No starter built, just a rehydrate fresh packet.

 

[DavidDetroit]

I did an 11% RIS and it didn't do anything out of the ordinary as far as krausen, came nowhere near the lid. Maybe a lot of people do a big starter.

 

[Brewdogpunk]

Forgot to add, I do have a ‘bigger jugs’ FV, to allow for extra headroom

 

[kodak79]

Forgot to add, I do have a ‘bigger jugs’ FV, to allow for extra headroom

Everyone loves big jugs

 

[kodak79]

This happened a day after I set my last one going. Liquor poured out if the fermenting chamber when I took the front off. I just gave it a bit of a clean and set it going again. And then it came out again so just let it carry on.

 

[DavidDetroit]

This happened a day after

If you don't mind, what kind of yeast addition (amount, etc), fermentation temperature and expected ABV did that? It looks like you allowed more than enough room.
Thanks.

 

[uDicko]

Pressurised fermentation help reduce the krausen? A few psi?

 

[kodak79]

If you don't mind, what kind of yeast addition (amount, etc), fermentation temperature and expected ABV did that? It looks like you allowed more than enough room.
Thanks.

That was 20g of yeast (but can't remember what type) into a 23l brew. Starting gravity was 1080 and target was 1018 (though there's another thread about this at the moment as it went up from 1020 before adding hops to 1028 when bottled). So about 8%. Set the temp to 20c but it tended to run at 22-23c under it's own steam. It dropped 54 points in the first 3 days.

 

[strange-steve]

There does seem to be something about dark worts and high gravity worts that turbocharges yeast activity. Put the two together as in an RIS, and the results are often explosive.

 

[samale]

There does seem to be something about dark worts and high gravity worts that turbocharges yeast activity. Put the two together as in an RIS, and the results are often explosive.

Add a Belgian yeast and you have lift off.

 

[DavidDetroit]

I've made seven Belgian tripels lately with an OG of 1.104 and an FG of 1.004. My plastic FV is 7.9 gallons and my batch size is 5 gallons. I get a krausen of about 2" each time. I cool the wort to 65°F-70°F and use 2 packs of MJ M-41. Ambient temperature of 67°F.
I believe people are getting giant reactions and there was even a photo of it but I'm not having that happen.

 

[Zephyr259]

Wow, thanks for all the advice folks. I'll not put this into the small FV...

@BeerCat I just used the last of my munich lager strain on a maibock, I could harvest some from the FV but probably simpler to just go with the scottish ale as planned and keep it cool since that one is happy down at 13c.

My wife has agreed that "too much" imperial stout probably isn't a problem so think I'll scale up and go for 15L in the conical. Thanks for the advice.

 

[Brewdogpunk]

Further to my previous post about combining a Youngs AM Porter and a Coopers Stout kit, I take it I should only use one of the yeasts to get this going?
That was always the plan, but reading some of the comments here I think it’s a must to start it off slowly